METHOD FOR OPERATING A MOTOR VEHICLE AND MOTOR VEHICLE

Abstract

A method for operating a motor vehicle including a traction electric motor, wherein the traction electric motor can be actuated for producing a creep torque that brings about a slow movement of the motor vehicle, wherein a plurality of creep torques of different magnitude can be set by a user of the motor vehicle.

Claims

1. A method for operating a motor vehicle comprising: a traction electric motor, wherein the traction electric motor can be actuated for producing a creep torque that brings about a slow movement of the motor vehicle, wherein in that a plurality of creep torques of different magnitude can be set by a user of the motor vehicle.

2. The method according to claim 1, wherein, when a setting condition is met and when a creep torque is present, the creep torque is deactivated when a brake system of the motor vehicle is actuated.

3. The method according to claim 2, wherein, in addition, at least one brake of the brake system of the motor vehicle is activated.

4. The method according to claim 1, wherein, when, if need be, an additional setting condition is met and depending on inclination information that describes a vehicle inclination, and status information that describes an operating state of the motor vehicle, at least one brake of the brake system of the motor vehicle is activated.

5. The method according to claim 3, wherein in that the activated brake is deactivated when an accelerator pedal of the motor vehicle is actuated.

6. The method according to claim 1, wherein the magnitude of the creep torque and/or the setting condition and/or, if need be, the additional setting condition can be set by a user of the motor vehicle via a user interface of the motor vehicle.

7. The method according to claim 6, wherein the user interface comprises at least one binary switch and/or one selector switch and/or one touchscreen and/or one speech recognition device.

8. The method according to claim 2, wherein, when, if need be, an additional setting condition is met and depending on inclination information that describes a vehicle inclination, and status information that describes an operating state of the motor vehicle, at least one brake of the brake system of the motor vehicle is activated.

9. The method according to claim 3, wherein, when, if need be, an additional setting condition is met and depending on inclination information that describes a vehicle inclination, and status information that describes an operating state of the motor vehicle, at least one brake of the brake system of the motor vehicle is activated.

10. The method according to claim 4, wherein in that the activated brake is deactivated when an accelerator pedal of the motor vehicle is actuated.

11. The method according to claim 2, wherein the magnitude of the creep torque and/or the setting condition and/or, if need be, the additional setting condition can be set by a user of the motor vehicle via a user interface of the motor vehicle.

12. The method according to claim 3, wherein the magnitude of the creep torque and/or the setting condition and/or, if need be, the additional setting condition can be set by a user of the motor vehicle via a user interface of the motor vehicle.

13. The method according to claim 4, wherein the magnitude of the creep torque and/or the setting condition and/or, if need be, the additional setting condition can be set by a user of the motor vehicle via a user interface of the motor vehicle.

14. The method according to claim 5, wherein the magnitude of the creep torque and/or the setting condition and/or, if need be, the additional setting condition can be set by a user of the motor vehicle via a user interface of the motor vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Further advantages and details of the invention ensue from the exemplary embodiments as well as on the basis of the drawings. Shown are:

[0018] FIG. 1 a schematic side view of a motor vehicle according to the invention and

[0019] FIG. 2 a flow chart of a method according to the invention.

DETAILED DESCRIPTION

[0020] Illustrated in FIG. 1 is a schematic side view of a motor vehicle 1 according to the invention. The motor vehicle 1 comprises a traction electric motor 2, which serves for driving the motor vehicle 1. Furthermore, the motor vehicle 1 comprises a brake system 3, which comprises wheel brakes 4, each of which is arranged at a wheel of the motor vehicle 1, as well as a parking brake 5, which is arranged at a rear axle of the motor vehicle 1. An actuation of the brake system 3, which results in an activation of the wheel brakes 4, can be carried out via a brake pedal 6. For manual actuation of the parking brake 5, furthermore, a handbrake lever 7 can be provided.

[0021] The traction electric motor 2 can be controlled via an accelerator pedal 8. Provided for carrying out a method according to the invention is a control device 9, which, for example, can be designed as part of a motor control device. The motor vehicle 1 comprises, furthermore, a user interface 10, which, for activation of functions and/or for setting the magnitude of a creep torque, comprises one binary switch or a plurality of binary switches 11 and/or a selector switch 12. Additionally or alternatively to this, an activation of functions and/or a setting of the magnitude of a traction element can also occur via a touchscreen 13 of the interface 10 and/or via a speech recognition device 14 of the user interface 10.

[0022] Through an actuation of the traction electric motor 2 by the control device 9, it is possible, regardless of the setting made by a user of the motor vehicle 1, to produce a creep torque, which brings about a slow movement of the motor vehicle 1. In this case, a setting of the magnitude of the creep torque can be made via the user interface 10 of the motor vehicle.

[0023] Illustrated in FIG. 2 is a flow chart of an exemplary embodiment of a method according to the invention. The steps presented represent the following:

TABLE-US-00001 S1 start S2 checking actuation of the accelerator pedal S3 activation of the creep torque S4 checking actuation of the brake system S5 checking the setting condition S6 deactivation of the creep torque S7 checking the additional setting condition S8 checking the inclination information S9 checking the status information S10 activation of the brake system

[0024] The method starts in step S1 when the operation of the motor vehicle begins. The beginning of the operation may take place, for example, when an ignition or a starting button or the equivalent is actuated.

[0025] In step S2, it is checked in an ongoing manner during operation whether an actuation of the accelerator pedal is present. If this is the case, then, as indicated by the yes arrow 15, the ongoing checking proceeds to check whether an actuation of the accelerator pedal 8 is present. If no actuation of the accelerator pedal 8 exists, then, as indicated by the no arrow 16, the checking proceeds with step S3 in a first branch 17 of the method.

[0026] In step S3, there occurs an activation of the creep torque depending on the magnitude set by the driver. If a set magnitude of the creep torque is present, then the checking proceeds with step S4.

[0027] In step S4, the operation of the motor vehicle occurs due to the creep torque. The motor vehicle 1 consequently moves slowly forward because of the creep torque produced by the traction motor 2. During step S4, it is checked in an ongoing manner whether an actuation of the brake system 3 is present. An actuation of the brake system 3 can occur, for example, if the driver actuates the brake pedal 6 and/or the handbrake lever 7. If no such actuation of the brake system 3 is present, then, as indicated by the arrow 16, the condition of step S4 is checked in an ongoing manner. If an actuation of the brake system 3 is present, then the checking proceeds with step S5.

[0028] In step S5, it is checked whether the setting condition is met. The setting condition is met when the driver has activated the corresponding autohold function via the user interface 10 of the motor vehicle 1. If the setting condition is not met or if the function is deactivated, then the creep torque is not deactivated and the checking proceeds with step S4. If the setting condition is met, then, in step S6, the deactivation of the creep torque is produced. Optionally, in addition, it is possible here to also provide in step S6 a steady activation of the brake system 3 when there is only a single actuation of the brake system 3. A deactivation of a brake system 3 that has been activated in a steady manner in such a way takes place in this case as soon as the accelerator pedal 8 is actuated.

[0029] In addition to the first branch 17 of the method, which describes an autohold function, a second branch 18 can be provided, which can be laid out in parallel to the branch 17.

[0030] If, in step S2, no actuation of an accelerator pedal is present, then, in the second branch 18, it is possible to proceed with step S7. Likewise, it is possible to proceed with step S7 if it has been established in step S3 that no creep torque is present or if a creep torque with a magnitude of zero is set. In step S7, it is checked whether the additional setting condition is met. This setting condition is met when the driver has activated the corresponding function, that is, the function of automatic holding on a hill described by the second branch 18. If this additional setting condition is met, then the checking proceeds with step S8. In step S8, it is checked whether the inclination information, which describes an inclination of the motor vehicle, describes a currently existing inclination of the motor vehicle. For this purpose, it is possible to check, for example, whether the inclination of the motor vehicle exceeds a given threshold. If this is the case, then, in step S9, it is subsequently checked whether the status information includes the fact that the vehicle is no longer moving forward or else is moving forward only at a speed produced by a creep torque. Furthermore, the status information can also describe whether an actuation of the accelerator pedal 8 is present. When no actuation of the accelerator pedal 8 is present and the motor vehicle is not moving or is moving only at a slow speed, then, in step S10, the activation of the brake system 3 occurs. A backward rolling of the motor vehicle 1 on a slope is thereby prevented. Subsequently, the method proceeds with the actuation of the accelerator pedal 8 in step S2. The method likewise proceeds in step S2 when one of the conditions checked in step S7, step S8, or step S9 is checked as not being met. In this case also, the method proceeds in step S2.

[0031] Obviously, it is possible for a method according to the invention to comprise only one of the two branches 17, 18.